Whales Migrate in Straight Lines    [06-05-2011] Traveling over 6,500 kilometers of ocean water off the East coast of Brazil (the Cook Islands and New Caledonia), humpback whales make their seasonal voyage to the cold waters of their Antarctic feeding grounds. Though their migratory paths have been charted by researchers in the past, recent studies have taken a closer look at just how well these whales know their way around the ocean. The results were astonishing. Scientists found that the humpback whales navigated the expansive waters with incredible accuracy. The whales never deviated off their regular path by more than a single degree. When they arrived at their destination, it was always within a 100-kilometer of the exact same spot as before. Whales boast the longest migrations of any mammalian species. The precision of their course is an impressive feat, considering the changing variables of weather and water conditions throughout their lengthy journey. So how do they stay on track? The answers are theoretical guesses, at best. Some researchers say that the whales use Earth’s magnetic field as a compass, while others suggest that they orient themselves using the sun as a guide. However, magnetism can vary and the sun is less reliant in water. The most likely is that the whales use both systems, but even this does not explain how whales can still travel so straight. Hopefully, by continuing to follow their path, we may discover how these huge mammals keep so steady and true!     출처: 어린이 영자신문 키즈타임즈 (www.kidstimes.net)